Do you determine the correct color strength?

There are number of methods for determining the color strength of pigment preparations. All methods have one thing in common: the color strength can only be determined in a defined mixture with white. This results from the Kubelka-Munk theory.

There are different procedures, but also different algorithms for calculation, which can lead to very different results – with fatal consequences in the further processing of the pigment preparations. Since color strength describes the coloring effect of a paste, it correlates with the concentration of the pigment. The color strength is therefore a proxy for the pigment concentration in the processed state.

However, the question arises as to which influencing factors of the individual methods provide reliable results. Deviations have a direct influence on the process and are one of the reasons why corrections are necessary in the production of color shades.

In the following, we describe a procedure that allows an objective evaluation of the methods. For this purpose, we create a concentration series around the commonly used mixing with white, in which the white portion is kept constant, and the colorant portion is varied in two steps to both lower and higher concentrations. This results in a concentration series of 5 measuring points whose colorant concentration is known. The color intensities of the 5 mixtures are now determined using the methods to be compared. The measurement results are plotted against the weighed-in concentration in each case.

In the following example of a blue pigment, the following mixtures were prepared and each measured dry with the squeegee applied (red line) and liquid with the Q-Chain® LCM-Mono (blue line). The measured color intensities are shown in the following graph:

In addition, the slopes of the straight lines are indicated in the graphic. A slope of 1 means that exactly the value corresponding to the initial weight is measured. In the example above, the liquid coating color measurement is close to the target value of 1, while the slope of the drying process is only 0.59. This means that the concentration deviation is measured incorrectly by 41%. As a result, any weighing of a recipe or any correction is also wrong. This process error is the cause of a large number of corrections.

You want to know how your own color strength determination stands? Then do the test in your plant. Download the tool from our website and do the test in your process.

Choosing the right algorithm is another aspect to consider. From a whole series of studies on mixing systems, we know that certain algorithms do not give useful results at all. Starting from the same spectrum, different calculation methods give very different values. The topic is extensive. We will write another post on this.

Do you want to know more about how you can reduce corrections in your operation? Then test the performance of your process!

Below you can download the tool after entering your eMail-Adress.

You want to know more? Write us or just give us a call!

Avoid corrections! Completely!

ISO 787-24 describes color strength as the ability of a pigment to absorb incoming light and thereby have the ability to color or darken, for example, a white color into which it is incorporated.

In practice, for a colored pigment, a batch of paste is mixed with a standard white in a defined ratio, applied and measured. A subsequent batch is processed in the same defined way. The spectra are then compared. So far, so good, if it weren’t for various basic conditions and influencing factors that make life difficult in practice.

On the one hand, there are the application methods:

  • Draw down
  • Spraying
  • Liquid color measurement, static
  • Liquid color measurement, dynamic

Problematic with the first two methods are the hiding power and gloss level and, from a process engineering point of view, the drying times. In static liquid coating color measurement, when the material is at rest during the measurement, adhesion or anti-drying effects can influence the measurement results. In all these methods, flocculation effects are common concomitants that also influence the results. In dynamic liquid paint color measurement, these effects do not have a major influence, but since it is a non-contact measurement of material in motion, the measurement distance and shear must be kept constant during the measurement. At ORONTEC, we have developed two measuring devices that enable the non-contact measurement of liquid films in a reproducible and accurate manner.

On the other hand, there are also different calculation methods:

  • Comparison of the value in the spectrum at maximum absorption.
  • Integral comparison of the area under the spectrum without weighting
  • Integral comparison of the area under the spectrum with weighting

Starting from exactly same spectrum, the differences in the results can be very different:

The example shows that not all methods deliver good results for every course of the spectra.

While similar values are displayed for the brightening power and the color strength of the “black”, the integral methods deliver very different values. Especially for the yellow paste, the deviation is very considerable. By means of mixing tests, it was confirmed that the weighted algorithm of ORONTEC delivers exactly the values that resulted in a small acceptable deviation. Completely without taking into account the color strength factors, a readjustment of the example color tone with the second set of mixing components had a deviation of dE* = 2.1. With taking into account the color strength factors of the weighted algorithm, The color difference is dE*=0.2 only.

A method to quantify the quality of the color strength determination will be content of the next blog post.

By definition, the color strength correlates directly with the concentration of a colorant. If the color strength is determined inaccurately or completely incorrectly, the result will be exactly the corrections that constitute its “hidden factory”. The method therefore has a direct influence on the commercial success of your production and your company. Anyone who measures color strength incorrectly or uses incorrectly measured values is giving money away.

In the next article, we will present a simple procedure for finding out how good your color strength method is.

You want to know more about this topic? Then follow our blog or give us a call.

Use your slumbering capacities!

Imagine being able to complete all your orders on the shop floor without corrections and on time by the specified deadline. Is this an illusion or can it become reality?

We believe it can become reality. And we also have concrete starting points and examples for this. For implementation, it is necessary to find the “hidden factory” in one’s own process.

The term hidden factory has been used since the mid-1980s. Since then, the definition has changed a few times. Therefore, I would like to briefly define the term as it is usually seen from a process optimization perspective.

From a process optimization point of view, the “hidden factory” represents the potential that cannot be used in a value-adding way due to non-value-adding steps in the established process.

Value-added steps are process steps that add value to the product in the process. This means that the product is refined by these steps and the customer is prepared to pay a higher price for it.

Non-value-added process steps are all the activities we do in our established process to bring deviating product characteristics into specification, to rearrange the flow to accommodate changing priorities, to free up equipment or machinery so that other manufacturing can be done, and so on.

Why do we do these non-value-added activities? Because we can’t do better with the resources and skills we have. This is not so much an accusation as a hint at which point you can find the entrance to use the “hidden factory”. In the following articles, we will take a closer look at the topic using the example of color tone correction and describe concrete approaches for optimizing productivity at low investment costs.

But first, let’s take a look at the coating production process:

The process diagram shows end-to-end production. This means that the production of a single batch contains all production stages from the raw material to the delivered product. Within this process chain, there is a defect propagation that leads to the first sample, which is checked in the laboratory, showing an intolerable deviation from the target values. In most cases, inadequate controls take place in the previous process steps.

The result is a process that follows the principle of “measure and correct”. Only at this point does the deviation from an ideal process become apparent. Often the number of corrections is between 4 and 6 cycles and requires between two hours and one day per cycle. This is exactly where the hidden factory lies. In practice, we are often confronted with the fact that these corrections are necessary in the end because process control at the front of the process is too time-consuming, lengthy and expensive.

In the following articles, we will take a closer look at the effects of this approach and what options there are to use the hidden factory and to come to a principle of “Measure and Control”. Having the process under control from the beginning is the way to use the “Hidden Factory”.

Want to know more, then follow our blog or give us a call.

ORONTEC at the 6th ECP – Online Partnering

International & Innovative Networking from February 16 to 18, 2022.

The ECP will take place for the sixth time in uninterrupted sequence since 2017. For two days, contacts can once again be made in a compact and concentrated manner in the proven partnering, cooperations can be initiated and the major content-related challenges of the future can be discussed, with an accompanying program: workshops, pitches, panels & networking.

Once again, SMEs will meet with large companies, investors and service providers for Business Partnering with an attractive accompanying program including keynote speeches, pitches, break-out sessions, workshops, networking and a closing panel. Several flash sessions will again allow attendees to introduce themselves in one-minute pitches, initiating informal networking.

ORONTEC is excited to participate as an innovator in digitization & automation and as an expert in colorimetry & color measurement. We take this opportunity to discuss innovative ideas and how they can be implemented, thus doing our part to help shape the industry. The networking potential of this event is great and has already proven itself for us in the past.

You are interested?


Click here for 6th ECP

 

Our workshops in the overview

Customized knowledge for our customers

“All things are hard before they become easy,” the English historian Thomas Fuller once said. With our workshops covering a wide range of topics in the coatings and paint industry, we want to help you master even major challenges with ease. Our experts impart their specialist knowledge in a practical way – either at your premises or via an online appointment. Are you ready for a brief overview of the current workshops?

Complaints – how to deal with them skilfully

The customer is king. But what do you do when the king complains? With tools and guidelines, we help you develop optimized workflows for this unpleasant but also unavoidable situation. This is how you turn dissatisfied customers into satisfied customers again.

Personnel – make optimal use of your employees

The shortage of skilled personnel is also affecting the painting and color industry. We show you how to make ideal use of existing personnel in order to relieve them. We also uncover optimization potential through training to improve your workflows. . The result is an action plan for personnel development, optimal workload and improved internal communication.

Fast order processing – so you are always one step ahead of competitors

Order acceptance, production, delivery – if delays occur in this process chain, there is a risk that your customers will switch to faster market competitors. Stop putting valuable customer relationships at risk. Together, we subject every step from order acceptance to finished processing to a critical review so that you have the decisive advantage on your side..

Digitization for your purchasing

Imagine your purchasing and development department as well as product management working optimally hand in hand when it comes to information on raw materials and suppliers, for example. Because great potentials for improved workflows lie in a reduction of silos! We show you how you can realize an interlocking of these departments and profit from it. For a better overview and more success.

How to: Digitization 4.0

Everyone is talking about it, but how do you digitize a paint factory? We identify dormant potential and explain how you can uncover it. Whether for purchasing, production or development – the intelligent paint factory helps you to significantly increase your efficiency.

Mystery colorimetry? Not with us!

In this workshop, we will teach you the basics you need to gain a basic understanding of color measurement. Learn in a practical and easy-to-understand way how to implement optimal color management – without an overly academic approach.

How to use your data treasures

In the digital age, data is rightly considered the new oil. We help you to better utilize relevant data from your company to make essential processes more efficient. For maximum success with minimum effort. To achieve this, we combine 150 years of experience in coating development and IT expertise.

Optimize dispersion

Dispersion is not without reason the process in the coatings industry with the highest added value. In our hands-on workshop, you will learn how to make optimum use of the aggregates employed for this purpose. In this way, you will achieve ideal capacity utilization and benefit from particularly efficient use of raw materials without this being at the expense of product quality.

Throughput times – make optimal use of the precious resource “time”

For companies, time is money. So don’t give away cash and discover free time resources thanks to our workshop. To do this, we analyze your throughput times and support you in better exploiting your existing or unused potential.

Accelerate your coating development process

How do you master the balancing act between an ever greater variety of raw materials on the one hand and ever higher customer requirements on the other? In our workshop, we present solution strategies that range from customer support to innovation strategy, depending on the focus. The result: You benefit from significantly accelerated coating development.

A meeting with experts, a lecture, an award

… the SURCAR CONGRESS 2021 in Detroit was a great success.

The SURCAR CONGRESS is the event for the global body paint community. It was first held in 1964 and has since grown from a two-day convention to a global brand for the body and paint industry with a portfolio of events around the world.
SURCAR is all about helping the automotive paint industry and its associated companies stay connected, explore new channels and markets, and share the latest trends and information.

It quickly became clear again this year that the automotive industry continues to set new standards in application technology. One of the core topics of this conference was, for example, brownfield projects, in which automated paint shops are converted from old to new in a very short time – and which are being implemented by more and more companies.

ORONTEC’s contribution was also very well received at SURCAR. In his presentation “Digitalization and AI – how can new methods support the process of automotive painting?”, Ralph J. Wörheide was able to impressively demonstrate the ideas and measures with which ORONTEC is breaking new ground in the following areas

  • the use and application of further sensor technology in application systems
  • the modeling for artificial intelligence by ORONTEC technologies
  • the sharing of data along the entire process chain, from raw materials to application

His presentation not only inspired the participants, but also earned ORONTEC an award of which we are extremely proud: We were awarded the SURCAR Award for Grand Challenge. With this award, SURCAR honors the most innovative start-ups. Or established companies that develop new solutions for the automotive paint industry – like ORONTEC.

What painted panels can tell you

Do you know this? Two identical panels have been coated with the same paint and still look different. This is more than an annoying mistake, because the whole thing can quickly turn into an economic problem, because no customer is satisfied with such coating results.
But why do these different painting results occur? And what can be done to prevent this from happening in the first place? We have an idea…

For digital measurement of painted sheets and plates.

The Q-Chain® Surface Scanner Automatic is an automatic measuring machine that inspects painted panels for different characteristics using various measuring instruments and evaluates them statistically with integrated software.
From a loadable magazine, the panels are transported to the measuring station, where they are measured and then transferred to the output magazine.

In other words, the Q-Chain® Surface Scanner Automatic establishes a relationship between appearance and properties such as coating thickness, cloudiness and color intensity according to DIN EN ISO 28199 (2).

Modular design, versatile use.

One machine, many results: Because the Q-Chain® Surface Scanner Automatic can be operated with up to five commercially available measuring devices, you obtain concrete statements about the examined characteristics of the coating and their interrelationship.
Based on this evaluation, you can then precisely define tolerances and ranges so that the coating always achieves the desired result.

Here you can get more information about the Q-Chain® Surface Scanner Automatic:

 

MagnoMeter™ XRS

How to avoid errors in particle characterization.

Among particles, there are only identical twins – one might think so, if one looks at the traditional methods for particle characterization and surface analysis of dispersions. This is because these measurements assume that all particles are basically spherical and smooth – although this is rarely the case in most industrial materials. Another assumption is that particles are always uniform and homogeneous – which is also not always true.

Due to these faulty assumptions, the measured particle size – and thus the calculated surface area value – can be misleading. And this leads to consequential errors in subsequent application and use.

This is how the optimal surface determination succeeds.

Such annoying and costly errors can be easily prevented by using an instrument for particle characterization that works with NMR technology and therefore makes no assumptions about particle size or shape – such as the MagnoMeter™ XRS distributed by ORONTEC in Germany, which delivers first-class results in many different fields of work.

Whether in research or development, for quality control or assurance, or for process control laboratories, the MagnoMeter™ XRS is an effective and, above all, versatile tool. It not only assists in the quality control of incoming raw materials, but can also be easily used for monitoring the intermediate manufacturing process, quality assurance of final products and determination of shelf life.

A small device with big advantages.

Anyone who wants to be on the safe side when it comes to surface determination will find the MagnoMeter™ XRS the perfect helper – especially because the device not only delivers reliable results, but is also extremely uncomplicated to use:

  • Sample preparation is not necessary: All technically relevant and industry-relevant concentrations can be measured directly without dilution.
  • The measurement takes place virtually in real time. Depending on the sample, the result is available in one second, or after two minutes at the latest.
  • The instrument requires very little space on the laboratory bench, and there are many configuration options for the MagnoPod™ and control module.


If you would like to benefit from further tips and information on the topic of “Measuring methods in the paint and coatings industry”, simply take a look at our newsletter. Or come back to our homepage: In our blog, we report at regular intervals on innovative solution proposals that are sure to be of interest to your company as well.

Fraunhofer Institute, PolyShear prototype and ORONTEC

If you place the highest demands on research and science, you will end up, sooner rather than later, at the Fraunhofer Institutes, where application-oriented research is carried out for the direct benefit of companies.

This is also where, on behalf of a well-known car manufacturer and a well-known paint manufacturer, the “PolyShear” test ring line was developed, which can simulate the shear stress of a paint on a laboratory scale and thus provide a prognosis as to whether the tested paint system is suitable for a particular ring line.

The test ring line of Fraunhofer IFAM

In the test ring line of the Fraunhofer Institute’s paint technology experts, the paint is subjected to just as much stress as later in practical operation, despite the short distances. This circular test facility allows the paint system to be run continuously or in a stitch. Temperature control of the ring line is possible up to 40 °Celsius, and during loading, temperature, pressure, flow rate and shear rate can be measured and documented online at different points. In this way, for example, changes in viscosity as a result of a new coating batch or excessive pumping in the ring line can be measured directly. And although the test ring line requires only one liter of coating, it subjects the material to shear in accordance with the test specification and thus fulfills the function of a complete ring line system.

From prototype to product – thanks to ORONTEC

After the Fraunhofer Gesellschaft had patented this test system, they looked for a competent partner for further exploitation. This partner was to further develop the “PolyShear” test ring line to series production readiness and then produce and distribute it. And this is exactly where ORONTEC came into play.

As a leading provider of digital system solutions for measurement methods in the
paint and coatings industry, ORONTEC has the necessary expertise, experience and network to turn a promising prototype into a successful product.
The result: the Q-CHAIN ® POLYSHEAR, the innovative test ring line in which the know-how of the Fraunhofer Institute and the expertise of ORONTEC are optimally combined.

If you need more info about the Q-CHAIN ® POLYSHEAR:

 

Do you know the way to the optimum painting process?

Every operator of a paint shop is probably familiar with the problem that errors or irregularities repeatedly creep into the process and can only be eliminated again with a great deal of reworking and coordination with suppliers. But is this an irrefutable law of nature? We think not – and describe here how this “operational accident” can be cleverly circumvented and which innovative measurement methods offer optimum support in this respect.

In principle, one should for success:

  • consider the entire process chain and not just their own.
  • do not aim for retrospective quality control, but for prospective and proactive process control.
  • include the customer requirement already in the development phase.

Control of the material

To be on the safe side right from the start, the properties of the material should be examined very early in the process. The task of measuring a color as it is present in the liquid paint due to pigments, binders and additives is performed by the Q-Chain LCM system. The paint is applied to a rotating disk and the spectrum is then measured without contact from three angles. Various color data can be determined from the spectra. Since the material is examined in its liquid state, a major source of process scattering, the influence of the coating, can be excluded.

The study of the coating

During further processing of the coating material, the process result depends on some measurable parameters. For example, in order to evaluate coating systems, a correlation is established between the appearance and the coating thickness – a job for the Q-Chain® Surface Scanner Automatic. It measures test sheets that have previously been painted with a coating thickness gradient. This provides information about the coating thickness range in which the painting process will produce the desired results. The coating thickness can then be used as a control variable in the subsequent application process.

The advantage of process optimization

In addition to the corresponding measurement technology, production systems support the alignment of processes to a prospective and proactive approach. With Flow2Grow®, an optimization approach related to the paint and coatings industry has now been developed for the first time. The system uses a combination of statistical methods, project management tools and optimized measurement technology.

The combination of these different optimizations makes it possible to almost completely eliminate material-related coating defects – a goal that should definitely be strived for in view of the ever-increasing demands on quality, speed and efficiency of production processes.


If you are interested in what other ideas we can use to optimize processes in the paint and coatings industry, just take a look at our newsletter. Or drop by here again sometime. We will report regularly on this in our blog.